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Sneezeweed (Helenium hoopesii)
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Sneezeweed (Helenium hoopesii)Animals that feed on sneezeweed may become affected with "spewing sickness". The disease gets its name from its most characteristic sign -- chronic vomiting or spewing. In the Western States, western sneezeweed is common to many mountain ranges. Sheep are frequently poisoned by sneezeweed; cattle are rarely poisoned. Animals eat sneezeweed during the summer and fall, when other forage is scarce or has become less palatable. All plant parts are poisonous.

Sneezeweed has one or several stems. Leaves are alternate, lance shaped, and smooth edged. Orange flowers with darker orange centers grow in clusters. Sneezeweed is a perennial of the sunflower family and is closely related to bitterweed and Colorado rubberweed

Distribution of sneezeweed

Where and When It Grows
Sneezeweed grows at elevations of 1500 to 4,000 meters on moist slopes and well-drained meadows from western Montana and eastern Oregon southward to California and New Mexico. It starts growing in early spring and matures in the late summer and early fall. It generally is between 0.5 and 1.0 meters tall. Sneezeweed increases with range misuse. Heavy stands of sneezeweed will inhibit the growth of other plants.

How It Affects LivestockSneezeweed grows on high mountain meadows and hillsides.
An animal may die if it eats small quantities of sneezeweed over a long period. Eating about 1 kg of green sneezeweed leaves daily for 10 days may poison sheep. Some animals die within a few days after first signs appear. Others that develop a chronic form of poisoning may live for 2 to 3 weeks. Complete recovery from the poisoning is possible if animals are taken off the plants as soon as the first signs are observed.

Signs and Lesions of Poisoning

  • Decreased appetite
  • Lips may become stained green from vomiting
  • Lambs may become stiff and wasted
  • Depression
  • Weakness with irregular pulse
  • Frothing at the mouth
  • Coughing
  • Emaciation and wasting
  • Ascites
  • Gastrointestinal hyperemia
  • Renal tubular necrosis
  • Liver degeneration

    How to Reduce Losses
  • Alternate grazing of sneezeweed (on-and-off) in infested areas.
  • As soon as signs of poisoning appear, remove all animals from sneezeweed-infested
       range for 10 to 14 days. Lambs are good indicators as they usually show signs of
       stiffness before other symptoms appear in older sheep. Lambs left to graze
       sneezeweed after signs first appear become unthrifty and unprofitable to keep. Ewes
       left on sneezeweed after signs appear will waste and die.
  • Practice open herding, allowing animals free movement to select more desirable
       plants.  Prevent overgrazing and forcing animals to eat sneezeweed due to lack of
       better forage.  Improve range condition to reduce snakeweed density.
  • Sneezeweed can be controlled with 2,4-D at 4 lb/ac.  Follow all precautions for
       handling herbicides.